This invention relates generally to the field of electronic devices and systems, and more specifically to optical switching technology.
A relay or switch may be used to change an optical signal from a first state to a second state. In general there may be more than two states. In applications that require a small switch geometry or a large number of switches within a small region, micromachining fabrication techniques may be used to create switches with a small footprint. A micromachined switch may be used in a variety of applications, such as industrial equipment, telecommunications equipment and control of electro-mechanical devices such as ink jet printers.
In switching applications, the use of piezoelectric technology may be used to actuate a switch. Piezoelectric materials have several unique characteristics. A piezoelectric material can be made to expand or contract in response to an applied voltage. This is known as the indirect piezoelectric effect. The amount of expansion or contraction, the force generated by the expansion or contraction, and the amount of time between successive contractions are important material properties that influence the application of a piezoelectric material in a particular application. Piezoelectric material also exhibits a direct piezoelectric effect, in which an electric field is generated in response to an applied force. This electric field may be converted to a voltage if contacts are properly coupled to the piezoelectric material. The indirect piezoelectric effect is useful in making or breaking a contact within a switching element, while the direct piezoelectric effect is useful in generating a switching signal in response to an applied force.
A method and structure for an optical switch is disclosed. According to the structure of the present invention, a liquid-filled chamber coupled to a plurality of optical waveguides is housed within a solid material. Seal belts within the liquid-filled chamber are coupled to the solid material, while piezoelectric elements are coupled to a plurality of membranes. The plurality of membranes are coupled to the liquid-filled chamber. The plurality of seal belts are coupled to a plurality of liquid metal globules. A slug is coupled to one or more liquid metal globules and coupled to one or more of the plurality of seal belts. According to the method of the present invention, piezoelectric elements are actuated, causing membrane elements to be deflected. The deflection of the membrane elements changes a pressure of actuator liquid and the change in pressure of the actuator liquid breaks a liquid metal connection and a slug connection between a first contact and a second contact of the electrical switch, thereby blocking or unblocking one or more optical waveguides.